What is a tdf file and how do I open a tdf file?
Text documents saved in the TDF extension is commonly referred to as Guide text definition files. Guide is a software developed by Project Pluto as a Microsoft Windows-based program for planetarium and star mapping purposes. Users of Microsoft Windows-based systems can open, edit and view the content saved as files in the .tdf format with the Microsoft Notepad text editor as well as the Microsoft WordPad word processing software. These text definition files may be included in installer packages of the Planet Pluto Guide program or in installation CDs. These files in the TDF format are then stored in a directory inside the folder created during installation of the Guide software. Data contained in a TDF file is referenced by the Planet Pluto Guide software when a user views a map or chart associated with particular TDF documents using the Guide software. This means the system retains an optimal amount of available memory resources even when the Guide program is actively running, even if a user were looking at multiple star charts, because the program references associated TDF documents to display the correct data, which means those TDF files are not loaded unto the program itself.
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